Language in ROS_SELF_REG bsp page

Hi SRM'ites,

can i ask you one question?

We have scenario strategic sourcing of SRM 5.0.

How can the supplier change language on the ros_self_reg bsp page?

Even if supplier change the langauge on page system propose the same language that i defined in customizing of the service BSP.

Your help on this is apprecated

Alessio